For more than 10 years the Viking cruise ferry MV Mariella has been successfully operating her four S.E.M.T. Pielstick 12VPC2.6.diesel engines with Humid Air Motor technology. This year the, Norwegian owned, purse seiner/trawler and factory vessel MV Kvannøy built in 2002, was converted to Humid Air Motor operation. NOx emissions were reduced by 61.3 per cent, a saving of 50 ton annually. The HAM system operates by saturating the incoming turbocharger charge air with sea water vapor before it enters the air box and then the combustion chambers. The result is a lower peak temperature in the combustion process thereby reducing NOx formation. The economic benefits of the change gives a theoretical payback time for the HAM retrofit of approx. 3 years. [More]